Revealing mistake: As Machine Gun Joe runs slowly runs over a fisherman in a small brook, he stops and "peels out" on his head. You can see a film crewman in the driver's seat doing the actual carnage.
Revealing mistake: There are two actual games played out: one in Huston and one in Tokyo - the score board has identical faulty light bulbs in both locations.
Revealing mistake: Establishing shots of the party where Chaney will fight Pettibon's guy; when we see the band play and people dance, the footage is rather obviously stopped and reversed to give the impression of a longer shot (evidently they had too little usable film of the crowd dancing). (00:31:00)